docs: def basic_distance(trig_pin, echo_pin, celsius=20):
      '''Return an unformatted distance in cm's as read directly from
      RPi.GPIO.'''
  
      speed_of_sound = 331.3 * math.sqrt(1+(celsius / 273.15))
      GPIO.setup(trig_pin, GPIO.OUT)
      GPIO.setup(echo_pin, GPIO.IN)
      GPIO.output(trig_pin, GPIO.LOW)
      time.sleep(0.1)
      GPIO.output(trig_pin, True)
      time.sleep(0.00001)
      GPIO.output(trig_pin, False)
      echo_status_counter = 1
      while GPIO.input(echo_pin) == 0:
          if echo_status_counter < 1000:
              sonar_signal_off = time.time()
              echo_status_counter += 1
          else:
              raise SystemError('Echo pulse was not received')
      while GPIO.input(echo_pin) == 1:
          sonar_signal_on = time.time()
  
      time_passed = sonar_signal_on - sonar_signal_off
      return time_passed * ((speed_of_sound * 100) / 2)